September weather forecast
Stevensville, MT

Share

Weather in September

September, the first month of the autumn in Stevensville, is also an agreeable month, with an average temperature varying between 68°F (20°C) and 42.1°F (5.6°C).

Temperature

As Stevensville enters September, the average high-temperature decreases from the a moderately hot 77.5°F (25.3°C) of August to a pleasant 68°F (20°C). Stevensville experiences a drastic reduction from day temperatures to an average low of 42.1°F (5.6°C) in September.

Humidity

In Stevensville, the average relative humidity in September is 56%.

Rainfall

In Stevensville, during September, the rain falls for 7 days and regularly aggregates up to 0.55" (14mm) of precipitation. In Stevensville, during the entire year, the rain falls for 140.1 days and collects up to 15.16" (385mm) of precipitation.

Snowfall

Months with snowfall in Stevensville, Montana, are January through May, September through December. September is the first month it typically snows. Throughout September, in the average 0.2 snowfall days, it receives 0.2" (5mm) of snow. In Stevensville, during the entire year, snow falls for 87.7 days and aggregates up to 46.5" (1181mm) of snow.

Daylight

In Stevensville, the average length of the day in September is 12h and 32min.
On the first day of September, sunrise is at 6:57 am and sunset at 8:14 pm. On the last day of the month, sunrise is at 7:34 am and sunset at 7:17 pm MDT.

Sunshine

In Stevensville, the average sunshine in September is 9.5h.

UV index

In Stevensville, the average daily maximum UV index in September is 3. A UV Index estimate of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for the average person.
Note: The UV index of 3 during September translates into the following guidance:
Act with care - The suggestion to avoid sunburn is emphasized. Solar radiation is at its peak intensity during midday, so it's advisable to stay indoors or in the shade. Shield yourself from the harmful effects of UV radiation with sun-protective attire, a hat, and quality sunglasses. Be attentive! The reflective property of snow can nearly double the Sun's UV radiation.
Updated: Aug 26, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What is the usual temperature for Stevensville in September?

In September, in Stevensville, the average high-temperature is 68°F (20°C), and the average low-temperature is 42.1°F (5.6°C).

What is the average humidity in September in Stevensville?

In Stevensville, the average relative humidity in September is 56%.

How much does it rain in September?

In Stevensville, in September, during 7 rainfall days, 0.55" (14mm) of precipitation is typically accumulated.

When does it start to snow?

September is the first month it typically snows. Throughout September, in the average 0.2 snowfall days, it receives 0.2" (5mm) of snow.

What is the average length of the day in September?

In September, the average day length is 12h and 32min.

What time are sunrise and sunset in September?

On the first day of September in Stevensville, Montana, sunrise is at 6:57 am and sunset at 8:14 pm. On the last day of the month, sunrise is at 7:34 am and sunset at 7:17 pm MDT.

How many hours of sunshine does Stevensville have in September?

In Stevensville, the average sunshine duration in September is 9.5h.

What is the UV index reading in September?

The average daily maximum UV index in September is 3. A UV Index reading of 3 to 5 represents a moderate vulnerability from exposure to Sun's UV rays.
Average humidity
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Stevensville, MT

Average temperature in September - Stevensville, MT
  • Average high temperature in September: 68°F

The warmest month (with the highest average high temperature) is July (78.4°F).
The month with the lowest average high temperature is December (28.4°F).

  • Average low temperature in September: 42.1°F

The month with the highest average low temperature is August (48.7°F).
The coldest month (with the lowest average low temperature) is December (16°F).

Average pressure in September
Stevensville, MT

Average pressure in September - Stevensville, MT
  • Average pressure in September: 29.99"Hg

The month with the highest atmospheric pressure is January (30.2"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).

Average wind speed in September
Stevensville, MT

Average wind speed in September - Stevensville, MT
  • Average wind speed in September: 4.6mph

The windiest month (with the highest average wind speed) is January (5.4mph).
The calmest month (with the lowest average wind speed) is August (4.2mph).

Average humidity in September
Stevensville, MT

Average humidity in September - Stevensville, MT
  • Average humidity in September: 56%

The month with the highest relative humidity is January (87%).
The months with the lowest relative humidity are July and August (49%).

Average rainfall in September
Stevensville, MT

Average rainfall in September - Stevensville, MT
  • Average rainfall in September: 0.55"

The wettest month (with the highest rainfall) is February (1.93").
The driest months (with the least rainfall) are July and August (0.43").

Average rainfall days in September
Stevensville, MT

Average rainfall days in September - Stevensville, MT
  • Average rainfall days in September: 7 days

The month with the highest number of rainy days is March (17.5 days).
The month with the least rainy days is August (5.3 days).

Average snowfall in September
Stevensville, MT

Average snowfall in September - Stevensville, MT
  • Average snowfall in September: 0.2"

The month with the highest snowfall is February (11.22").
The months with the least snowfall are June, July and August (0").

Average snowfall days in September
Stevensville, MT

Average snowfall days in September - Stevensville, MT
  • Average snowfall days in September: 0.2 days

The month with the highest number of snowfall days is February (17.3 days).
The months with the least snowfall days are June, July and August (0 days).

Average daylight in September /
Average sunshine in September
Stevensville, MT

Average daylight in September / Average sunshine in September - Stevensville, MT
  • Average daylight in September: 12h and 3min

The month with the longest days is June (Average daylight: 15h and 48min).
The month with the shortest days is December (Average daylight: 8h and 42min).

  • Average sunshine in September: 9h and 3min

The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is January (Average sunshine: 5h and 30min).

Average sunshine days in September
Stevensville, MT

Average sunshine days in September - Stevensville, MT
  • Average sunshine days in September: 21.5 days

The month with the most sunshine days is July (23.3 days).
The month with the least sunshine days is February (6.9 days).

Average UV index in September
Stevensville, MT

Average UV index in September - Stevensville, MT
  • Average UV index in September: 3

The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is January (UV index 1).

Average cloud cover in September
Stevensville, MT

Average cloud cover in September - Stevensville, MT
  • Average cloud cover in September: 21

The month with the most cloud cover is February (Cloud cover 48).
The month with the least cloud cover is July (Cloud cover 13).

Average visibility in September
Stevensville, MT

Average visibility in September - Stevensville, MT
  • Average visibility in September: 6mi

The months with the highest visibility are May, June, July, August, September and October (6mi).
The months with the lowest visibility are January, February and December (4mi).

Stevensville, Montana, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location